You could ask the designer, but that might not be such an easy job, looking at the lines of it. I am also a little surprised at the absence of any skeg to keep what is a shallow vee boat with a fair bit of forefoot, tracking straight. It looks like a warped plane bottom, but can't be sure without seeing a lines plan, but I'd say it doesn't have the lines that would make an extension straight forward.

Below linked the Devlin Curlew 20 pics in big format for a good view on what's available, couldn't find a built one on the web, but guess Sam or Lee or Jim can easily give info about that, and about the possibilities for a ± 10% stretch or so.

From Sam's Design Notes...‘‘ . . . . This type of hull design with her vee bottom running from a relatively sharp entry and reducing in deadrise gradually to the stern where the deadrise aft is the flattest of the run allows for great performance in a variety of waters. We ran a full length spray rail all along her sides just above the waterline and this will help keep spray down when blasting about on a brisk day. . . . . ’’

For more room I would also look at the plans of the LOA* 18' to 30' 8" series of Graham Byrnes at B&BYacht Designs...

I am also considering stretching in length but not in beam - how would this affect the performance? I feel I need a little more room, but want a boat that retains the efficiency of the Panga designs.

Click to expand...

Devlin's designs are "stitch and glue" and assembly requires cutting hull panels to final shape before putting on the boat. If the design is stretched the panel shapes will not be a simple lengthwise scaling of panel shapes before scaling. You will need to obtain the new panel shapes by some other method. My recommendation is to email or call Sam Devlin with your questions and ask him if he would be interested in creating plans for a stretched version.

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